The Vertebral column Flashcards
What are the functions of the vertebral column
- stiffens the body axis and contributes to the maintenance of posture
- Facilitates locomotion by muscle attachment, flexion, extension and torsion
- Encloses and protects the spinal cord and accessory structures within the central canal;
- protects the soft structures of the neck, throax, abdomen and pelvis
What bones does the axial skeleton consist of?
Vertebral column, rib cage, skull
What are the vertebral formula that make up the vertebral column in the dog and cat?
- Cervical, Thoracic, Lumbar, Sacral, Caudal
- C7, T13, L7, S3, Cd 15-20 (varies)
- There are regional variations!
What are the bones of the vertebral column classed as?
Irregular bones.
What is the vertebral formula for the pig
C7, T14/15, L6/7, S4, Cd 20+
What is the vertebral formula for the sheep and goat
C7, T13, L6/7, S4, Cd 20+
What is the vertebral formula for the OX
C7, T13, L6, S5, Cd 20+
What is the vertebral formula for the Horse
C7, T18, L6, S5, Cd 20+
Describe the structure of the vertebra
- body -
- Vertebral foramen = hole above body = spinal cord
- Neural arch forms the V foramen: dorsal = lamina, lateral = pedicle
- Dorsal spinous process
- Lateral side: transverse process = largest in lumbar
- Caudal and Cranial articular surface
- Mamillary pricess on top of transverse process
Where is the articulation of adjacent vertebrae?
- Caudal articular facets sit inside cranial ones
- all joints are synovial: collateral ligaments
- When adjacent articulate = forms the intervertebral foramen on lateral aspect = spinal nerve comes out and separates into dorsal and ventral branches = innovate those msucles
- intevertebral disk = fibrous cartilgeous
What is the structure of the intervertebral disk?
- attachment to body
- Fibro cartilaginous structure = dense collagen fibre arranges in ciruclar layers
- Outer concentric fibreous ring = annulus fibrosus.
- Thinnest dorsally = weakness
- Provides stability
- Inner = nucleus pulposus = gelatinous cushion, provides shock absorption
When looking at radiograph of vertebral column what can you identify?
- Intervertebral disk = gap
What are the cervical vertebrae characterised as and why
- C1&C2 = atypical as don’t resemble the rest of the vertebrae
- C3-7 = typical
Talk about C1
- ATLAS
- Reduced body
- no spinous process dorsally
- Elongated transverse process on lateral aspects = wings
- Cranially articulates with occipital condyles of skull forms atlanto-occipital joint! YES JOINT
- Caudally articulates with AXIS
Talk about C2
- AXIS
- 2 bodies (body and dense that sticks out)
- Large Palpable dorsal elongated spinous process
- Articulates with C1 = Atlanto-Axial joint
- joint only allows lateral rotation: NO joint!
- Transverse foramen at top of transverse process = vertebral arteries
Describe C3 - C7
1.typical vertebrae C7 = pronounced projections ventrally 3. High flexion adn extension 4. Lateral movement 5. Transverse foramen
What is different about C7?
It lacks the transverse foramen exhibited by the other cervical vertebrae which is present in all other Cervical vertebrae!
Why do we have 7 cervical vertebrae but 8 cervical spinal nerves?
- In C region, each spinal nerve exits from the vertebral canal CRANIAL to the vertebra of the same number.
- In thoracic region, each spinal nerve exits CAUDAL to the vertebra of the same number
- Therefore this leaves a spinal nerve between the caudal C7 and cranial T1 = C8
How many cerviacle nerves?
7
Where is the majority of movement
Cerviacle and lumbar not thoracic. MOST = thoracolumbar junction
Facts about thoracic vertebrae
- have short body
- allow articulation of the bones of the rib cage
- Cranial and caudal costal fovea for articulation with ribs
- Small transverse process = to accomodate ribs
- Lateral costal fovea accomodates the ehad of the rib, tubercle of rib attaches onto costal fovea that lies ventral to transverse process
- Large dorsal elongated spinous process
What about the thoracic vertebrae projections
- T1 to T10 project caudally
- T11 - (vertical) anticlinal = perp
- Beyond: cranial angulation
Facts about lumbar vertebrae
- Longer bodies
- LArge transverse processes: project Cranially! whereby abdominal muscles attach
- allow flexion and extension
- large body
- LArge spinous process
6.
Facts about the sacral vertebrae
- vertebrae are fused = no movement, no discs
- one bony component
- Transverse process of S1 articulates with sacrael pelvic surface of ilium of pelvis
- Sacrotuberous ligament originates from last sacrael vertebrae
